Vehicular camera assembly process with dual focusing feature

ABSTRACT

A vehicular camera includes a lens barrel, a lens holder and an imager PCB. The lens barrel accommodates a lens and has a threaded inner end. The lens holder has a threaded passageway for threadedly receiving the threaded inner end of the lens barrel. The lens barrel is threadedly attached to the lens holder with a biasing element applying a biasing force at the lens barrel to urge the lens barrel in a direction outward away from the lens holder. The imager PCB is attached to the lens holder with an imager of the imager PCB facing the lens, and the imager PCB is adjusted relative to the lens holder and lens barrel construction to optically align the lens at the imager. After the imager PCB is secured relative to the lens holder, the lens barrel is rotated to adjust focus of the lens at the imager.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority of U.S. provisional applicationSer. No. 62/882,621, filed Aug. 5, 2019, which is hereby incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to a vehicle vision system for avehicle and, more particularly, to a vehicle vision system that utilizesone or more cameras at a vehicle.

BACKGROUND OF THE INVENTION

Use of imaging sensors in vehicle imaging systems is common and known.Examples of such known systems are described in U.S. Pat. Nos.7,965,336; 5,949,331; 5,670,935 and/or 5,550,677, which are herebyincorporated herein by reference in their entireties.

SUMMARY OF THE INVENTION

The present invention provides a driver assistance system or visionsystem or imaging system for a vehicle that utilizes one or more camerasto capture image data representative of images exterior of the vehicle.The camera includes a lens holder and an imager printed circuit board,with the imager printed circuit board fixed to the lens holder, and witha lens barrel (accommodating a lens or lens assembly therein) attachedat the lens holder. The camera also includes a rear housing thatattaches at the lens holder after the lens and imager are opticallyaligned and focused. The lens barrel is threaded partially into the lensholder and the imager printed circuit board is adhesively bonded to thelens holder with the lens and imager optically aligned. After the imagerprinted circuit board is bonded and secured at the lens holder and afterthe rear housing is attached at the lens holder to encase the printedcircuit board, the lens barrel may be rotated to adjust the focus of thelens and imager (such as in a fine adjustment manner to make very smalladjustments after alignment of the lens and imager). The camera includesa biasing element that maintains an outward force on the lens barrelrelative to the lens holder to compensate for any play or threadlooseness between the threaded lens barrel and the threaded lens holder.

These and other objects, advantages, purposes and features of thepresent invention will become apparent upon review of the followingspecification in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a vehicle with a vision system thatincorporates cameras in accordance with the present invention;

FIG. 2 is an exploded perspective view of part of a camera, showingthreaded engagement of the lens barrel into the lens holder tothreadedly attach the lens barrel at the lens holder, with the imagerand printed circuit board attached at the lens holder;

FIG. 3 is an exploded perspective view of part of another camera,showing engagement of the lens barrel into the lens holder to adhesivelyattach the lens barrel at the lens holder, with the imager and printedcircuit board attached at the lens holder;

FIG. 4 is an exploded perspective view of part of another camera,showing attachment of the lens barrel at the lens holder, with theimager and printed circuit board attached at the lens holder after thelens barrel is attached thereat;

FIG. 5 is an exploded perspective view of a camera that is assembled inaccordance with the present invention, showing the threaded lens barreland the adhesive dots for attaching the circuit board at the lensholder;

FIG. 6 is another exploded perspective view of the camera of FIG. 5,shown with the lens initially threaded into the lens holder, with abiasing force applied at the lens barrel to take up looseness in thethreads;

FIG. 7 is another exploded perspective view of the camera of FIG. 5,shown with the circuit board adhesively attached at the lens holder sothat the imager and lens are optically aligned;

FIG. 8 is another exploded perspective view of the camera of FIG. 5,shown with the rear camera housing attached and showing fine adjustmentof the lens barrel at the lens holder to adjust the focus of the lenswith the imager;

FIG. 9 is another exploded perspective view of the camera, showing thethreaded end of the lens barrel;

FIG. 10 is a perspective view of the lens barrel and lens holderconstruction; and

FIG. 11 is another perspective view of the lens barrel and lens holderconstruction, showing the inner end of the lens and the posts foradhesively bonding the imager circuit board at the lens holder.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A vehicle vision system and/or driver assist system and/or objectdetection system and/or alert system operates to capture images exteriorof the vehicle and may process the captured image data to display imagesand to detect objects at or near the vehicle and in the predicted pathof the vehicle, such as to assist a driver of the vehicle in maneuveringthe vehicle in a rearward direction. The vision system includes an imageprocessor or image processing system that is operable to receive imagedata from one or more cameras and provide an output to a display devicefor displaying images representative of the captured image data.Optionally, the vision system may provide display, such as a rearviewdisplay or a top down or bird's eye or surround view display or thelike.

Referring now to the drawings and the illustrative embodiments depictedtherein, a vehicle 10 includes an imaging system or vision system 12that includes at least one exterior viewing imaging sensor or camera,such as a rearward viewing imaging sensor or camera 14 a (and the systemmay optionally include multiple exterior viewing imaging sensors orcameras, such as a forward viewing camera 14 b at the front (or at thewindshield) of the vehicle, and a sideward/rearward viewing camera 14 c,14 d at respective sides of the vehicle), which captures images exteriorof the vehicle, with the camera having a lens (such as a plurality oflens optics at a lens barrel that is accommodated at the lens holder)for focusing images at or onto an imaging array or imaging plane orimager of the camera (FIG. 1). Optionally, a forward viewing camera maybe disposed at the windshield of the vehicle and view through thewindshield and forward of the vehicle, such as for a machine visionsystem (such as for traffic sign recognition, headlamp control,pedestrian detection, collision avoidance, lane marker detection and/orthe like). The vision system 12 includes a control or electronic controlunit (ECU) or processor 18 that is operable to process image datacaptured by the camera or cameras and may detect objects or the likeand/or provide displayed images at a display device 16 for viewing bythe driver of the vehicle (although shown in FIG. 1 as being part of orincorporated in or at an interior rearview mirror assembly 20 of thevehicle, the control and/or the display device may be disposed elsewhereat or in the vehicle). The data transfer or signal communication fromthe camera to the ECU may comprise any suitable data or communicationlink, such as a vehicle network bus or the like of the equipped vehicle.

Typically, active focus and alignment is used to set and secure a focalposition of a lens to an imager component. However, this leads toexpensive and complicated measures to manage the compliance tolerancescreated by camera components and manufacturing focus/alignment process.For example, and such as shown in FIG. 2, a camera may be assembledusing an active PCB alignment, which may use screws to secure the PCB tothe lens holder or front camera housing. After the PCB is secured to thelens holder, the lens barrel (such as a threaded lens barrel) isthreaded into the lens holder and used to set the focus of the lensrelative to the imager. After the lens and imager are optically alignedand focused (via threading the lens barrel into the lens holder), thelens barrel (and lens) is secured to the lens holder with adhesive onthe lens threads. This method by itself compensates for three degrees offreedom (X, Y, Z).

Optionally, and with reference to FIG. 3, active lens alignment may beprovided where the imager PCB is secured to the housing using screws andthe lens is actively moved to set focus and alignment, whereby a quickcure adhesive is used to set the focus and alignment of the lensrelative to the imager. The adhesive acts as a compliant material(before it is cured) to allow for focus and alignment, which is achievedby moving the lens relative to the lens holder. The UV and additionalcuring increases the tolerance stack of the finished assembly. Quickcure adhesives require UV+additional curing. This curing increases thetolerance stack of the finished assembly. This method by itselfcompensates for five degrees of freedom (X, Y, Z, U, V) and does notallow for rotational correction.

Optionally, and with reference to FIG. 4, active PCB focus and alignmentis achieved via a one piece lens assembly that is secured to the housingor lens holder utilizing adhesive initially, and then the imager PCB isactively moved relative to the housing or lens holder to set focus,alignment, and rotation, where a quick cure adhesive is used to set thefocus, alignment, and rotation. The adhesive (that bonds the circuitboard to the lens holder) acts as a compliant material (before it iscured) to allow for focus and alignment, which is achieved by moving thePCB relative to the lens holder. The UV and additional curing increasesthe tolerance stack of the finished assembly, and quick cure adhesivesrequire UV+additional curing. This curing increases the tolerance stackof the finished assembly. This method compensates for six degrees offreedom (X, Y, Z, U, V, W).

Referring now to FIGS. 5-11, an alternative build assembly processutilizes two focus and alignment methods, which allows for all degreesof freedom to be compensated for with adjusting the PCB forfocus+alignment+rotation and with an additional fine tune or adjustmentoption (if needed if testing of the assembled camera indicates that thelens is not properly focused relative to the imager) to rotate athreaded lens to adjust the focus after all curing or additionalprocesses are finished. The lens holder or threaded lens has a biasingelement or spring load to compensate for thread looseness. The activePCB focus+alignment+rotation allows for a maximum of six degrees offreedom (X, Y, Z, U, V, W) of compensation. Final fine tuning of thethreaded lens reduces the tolerance stack of the finished assembly bymaking a final focus adjustment after the curing or other processes.

As shown in FIG. 5, the lens barrel 30 accommodates a lens or lensassembly (comprising a plurality of lens optics or elements) and has athreaded inner end 30 a, which is threadedly received in a threadedpassageway 32 a of a lens holder or front camera housing 32. The imageris disposed at a front side of an imager printed circuit board 34, whichis adhesively bonded at four posts 32 b (such as via adhesive dots 36)that protrude from a rear side of the lens holder 32.

The assembly process starts by threading the lens barrel to apredetermined or selected distance into the lens holder (see FIGS. 5, 6and 9), with a force “F” applied to the lens barrel in the directionaway from the lens holder to reduce or limit or eliminate potentiallooseness between the lens holder and the lens barrel. The force may beapplied via a biasing element at the lens holder or lens barrel (such asa compressible elastomeric element or spring element that iscompressible and biased toward its uncompressed state). After the lensbarrel is positioned at the lens holder (FIGS. 6, 10 and 11), theadhesive 36 is applied at either the posts 32 b (and/or the posts mayhold the adhesive therein or thereat) or at the front side of the imagerPCB 34. With the PCB adhesively coupled to the lens holder via theadhesive (FIG. 7), the PCB is moved relative to the lens holder and lensto optically align and focus the lens and imager. The adhesive 36 actsas a compliant material to allow for six axis focus and alignment of thelens and imager. After the lens is optically aligned and focused at theimager, UV and additional curing means are applied to cure the adhesiveand secure the PCB 34 at the lens holder 32.

The rear camera housing 38 (including an electrical connector portion 38a that is configured to electrically connect to a header connector atthe PCB and to a vehicle wire harness) is attached (such as viafasteners or adhesive or welding) at the mating surface of the lensholder 32 to complete the assembly of the camera housing and to encasethe PCB within the camera housing (FIG. 8). At this time, the PCBadhesive 36 is fully cured or at least substantially cured to its curedstate, and any additional components (brackets, etc.) may be added tothe camera assembly. The final fine tune focus adjustment of the lensrelative to the imager is then achieved, if necessary, by rotating thelens relative to the lens barrel to more accurately fine tune the focus.For example, the camera may be tested to verify the proper focus of thelens at the imager and, if any correction or adjustment is needed,rotation of the lens may adjust or finely adjust the camera's focus asthe final step of the camera assembly process.

The final adjustment of the lens barrel (and lens) is facilitated sincethe lens barrel is not adhesively secured in the lens holder. The springloading of the lens barrel takes up or accommodates for any looseness inthe threads of the lens barrel and lens holder, and helps to retain thelens barrel relative to the lens holder. Thus, the lens barrel and lensholder construction allows for post-assembly fine tuning and fineadjustment of the lens to accommodate for any movements that may haveoccurred between the PCB and the lens holder during the assembly andcuring processes.

Optionally, an adhesive may be applied at the lens barrel and lensholder to further retain and secure the lens barrel at the lens holderafter the fine tuning process is completed. Optionally, such as anadhesive may be applied before or during the lens barrel attachment tothe lens holder, with the lens barrel adhesive being cured via adifferent means than the PCB adhesive, such that the lens barreladhesive is not cured until after the camera is assembled and after thelens barrel is finely tuned to achieve optimal focus and alignment ofthe lens to the imager. The adhesive or epoxy may be applied to fill thethreads between the lens barrel and the lens holder to seal the lensbarrel at the lens holder.

The biasing force may be applied via any suitable means, such as via apliable or compliant compound or element disposed in the threads or viaa spring element or compressible or deformable element or pliableelement or material (such as a deformable or compressible elastomericmaterial such as rubber) disposed at the lens holder and acting on theinner end of the lens barrel when the lens barrel is threaded into thelens holder. Optionally, the biasing force may be applied via a springelement or compressible or deformable element or pliable element ormaterial (such as a deformable or compressible elastomeric material suchas rubber) or the like disposed at the imager PCB and acting on theinner end of the lens barrel when the imager PCB is positioned at andadhesively bonded to the lens holder.

Although shown as having a single printed circuit board (having theimager at one side and circuitry and connecting elements (such as aheader connector) at the other side), the camera assembly may include animager printed circuit board and a separate connector printed circuitboard, with the circuitry of the two printed circuit boards electricallyconnected. The printed circuit boards may be attached at the lens holderor to the rear camera housing, and/or may be attached to one another,such as by utilizing aspects of the cameras and processes described inU.S. Pat. No. 10,676,041, which is hereby incorporated herein byreference in its entirety. The imager is aligned with the lens at thelens holder and the lens is optically aligned and focused with theimager and the housing portions are joined or bonded, such as byutilizing aspects of the cameras and processes described in U.S. Pat.Nos. 10,272,857; 10,264,219; 9,451,138; 9,277,104 and/or 8,542,451,which are hereby incorporated herein by reference in their entireties.

The camera may include electrical connecting elements that accommodatetolerances in the housing and/or PCB mounting and/or connector portion.The electrical connecting elements may utilize aspects of the camerasand electrical connectors described in U.S. Pat. No. 9,233,641 and/orU.S. Publication Nos. US-2013-0242099; US-2014-0373345; US-2015-0222795;US-2015-0266430; US-2015-0365569; US-2016-0037028; US-2016-0268716;US-2017-0133811; US-2017-0295306 and/or US-2017-0302829, which arehereby incorporated herein by reference in their entireties. Optionally,the electrical connections may be established via molded interconnectdevice (MID) technology, such as by utilizing aspects of the camerasdescribed in U.S. Publication Nos. US-2018-0072239; US-2017-0295306and/or US-2016-0037028, which are hereby incorporated herein byreference in their entireties.

The system includes an image processor operable to process image datacaptured by the camera or cameras, such as for detecting objects orother vehicles or pedestrians or the like in the field of view of one ormore of the cameras. For example, the image processor may comprise animage processing chip selected from the EYEQ family of image processingchips available from Mobileye Vision Technologies Ltd. of Jerusalem,Israel, and may include object detection software (such as the typesdescribed in U.S. Pat. Nos. 7,855,755; 7,720,580 and/or 7,038,577, whichare hereby incorporated herein by reference in their entireties), andmay analyze image data to detect vehicles and/or other objects.Responsive to such image processing, and when an object or other vehicleis detected, the system may generate an alert to the driver of thevehicle and/or may generate an overlay at the displayed image tohighlight or enhance display of the detected object or vehicle, in orderto enhance the driver's awareness of the detected object or vehicle orhazardous condition during a driving maneuver of the equipped vehicle.

Optionally, the camera may comprise a forward viewing camera, such asdisposed at a windshield electronics module (WEM) or the like. Theimager PCB and lens holder and lens construction may be disposed at andelectrically connected to a processor PCB of the camera module, such asvia a flexible electrical connector, with the lens barrel disposed at orprotruding through an aperture at an upper housing portion. The forwardviewing camera may utilize aspects of the systems described in U.S. Pat.Nos. 9,896,039; 9,871,971; 9,596,387; 9,487,159; 8,256,821; 7,480,149;6,824,281 and/or 6,690,268, which are all hereby incorporated herein byreference in their entireties.

Changes and modifications in the specifically described embodiments canbe carried out without departing from the principles of the invention,which is intended to be limited only by the scope of the appendedclaims, as interpreted according to the principles of patent lawincluding the doctrine of equivalents.

The invention claimed is:
 1. A vehicular camera configured to bedisposed at a vehicle so as to have a field of view exterior of thevehicle, the vehicular camera comprising: a lens barrel accommodating alens, the lens barrel having a threaded inner end; a lens holdercomprising a threaded passageway for threadedly receiving the threadedinner end of the lens barrel; an imager printed circuit board, whereinthe imager printed circuit board comprises a first side and a secondside opposite the first side and separated from the first side by athickness of the imager printed circuit board, and wherein an imager isdisposed at the first side of the imager printed circuit board; whereinthe lens barrel is threadedly attached to the lens holder, and wherein abiasing element applies a biasing force at the lens barrel to urge thelens barrel in a direction outward away from the lens holder; whereinthe imager printed circuit board is attached to the lens holder with thefirst side of the imager printed circuit board and the imager facing thelens, and wherein the imager printed circuit board is adjusted relativeto the lens holder and lens barrel construction to optically align thelens at the imager; wherein, after the imager printed circuit board issecured relative to the lens holder, the lens barrel is rotated toadjust focus of the lens at the imager; and a rear housing that is matedwith the lens holder to encase the imager printed circuit board.
 2. Thevehicular camera of claim 1, wherein the lens barrel is rotated toadjust focus of the lens at the imager after the rear housing is matedwith the lens holder.
 3. The vehicular camera of claim 1, wherein therear housing is mated with the lens holder after the imager printedcircuit board is attached to the lens holder.
 4. The vehicular camera ofclaim 1, wherein an electrical connector portion of the rear housing isconfigured to electrically connect to a wire harness of a vehicleequipped with the vehicular camera.
 5. The vehicular camera of claim 1,wherein the biasing element comprises a compressible elastomericmaterial.
 6. The vehicular camera of claim 5, wherein the compressibleelastomeric material comprises a rubber material.
 7. A vehicular cameraconfigured to be disposed at a vehicle so as to have a field of viewexterior of the vehicle, the vehicular camera comprising: a lens barrelaccommodating a lens, the lens barrel having a threaded inner end; alens holder comprising a threaded passageway for threadedly receivingthe threaded inner end of the lens barrel; an imager printed circuitboard, wherein the imager printed circuit board comprises a first sideand a second side opposite the first side and separated from the firstside by a thickness of the imager printed circuit board, and wherein animager is disposed at the first side of the imager printed circuitboard; wherein the lens barrel is threadedly attached to the lensholder, and wherein a biasing element applies a biasing force at thelens barrel to urge the lens barrel in a direction outward away from thelens holder; wherein the imager printed circuit board is attached to thelens holder with the first side of the imager printed circuit board andthe imager facing the lens, and wherein the imager printed circuit boardis adjusted relative to the lens holder and lens barrel construction tooptically align the lens at the imager; wherein, after the imagerprinted circuit board is secured relative to the lens holder, the lensbarrel is rotated to adjust focus of the lens at the imager; wherein thebiasing element comprises a compressible elastomeric material; andwherein the biasing element is disposed at least partially betweenthreads of the threaded inner end of the lens barrel and threads of thethreaded passageway of the lens holder.
 8. The vehicular camera of claim5, wherein the biasing element is disposed at the lens holder and actson the threaded inner end of the lens barrel when the threaded inner endof the lens barrel is threaded into the threaded passageway of the lensholder.
 9. A vehicular camera configured to be disposed at a vehicle soas to have a field of view exterior of the vehicle, the vehicular cameracomprising: a lens barrel accommodating a lens, the lens barrel having athreaded inner end; a lens holder comprising a threaded passageway forthreadedly receiving the threaded inner end of the lens barrel; animager printed circuit board, wherein the imager printed circuit boardcomprises a first side and a second side opposite the first side andseparated from the first side by a thickness of the imager printedcircuit board, and wherein an imager is disposed at the first side ofthe imager printed circuit board; wherein the lens barrel is threadedlyattached to the lens holder, and wherein a biasing element applies abiasing force at the lens barrel to urge the lens barrel in a directionoutward away from the lens holder; wherein the imager printed circuitboard is attached to the lens holder with the first side of the imagerprinted circuit board and the imager facing the lens, and wherein theimager printed circuit board is adjusted relative to the lens holder andlens barrel construction to optically align the lens at the imager;wherein, after the imager printed circuit board is secured relative tothe lens holder, the lens barrel is rotated to adjust focus of the lensat the imager; wherein the biasing element comprises a compressibleelastomeric material; and wherein the biasing element is disposed at theimager printed circuit board and acts on the threaded inner end of thelens barrel when the imager printed circuit board is attached to thelens holder.
 10. A vehicular camera configured to be disposed at avehicle so as to have a field of view exterior of the vehicle, thevehicular camera comprising: a lens barrel accommodating a lens, thelens barrel having a threaded inner end; a lens holder comprising athreaded passageway for threadedly receiving the threaded inner end ofthe lens barrel; an imager printed circuit board, wherein the imagerprinted circuit board comprises a first side and a second side oppositethe first side and separated from the first side by a thickness of theimager printed circuit board, and wherein an imager is disposed at thefirst side of the imager printed circuit board; wherein the lens barrelis threadedly attached to the lens holder, and wherein a biasing elementapplies a biasing force at the lens barrel to urge the lens barrel in adirection outward away from the lens holder; wherein the imager printedcircuit board is attached to the lens holder with the first side of theimager printed circuit board and the imager facing the lens, and whereinthe imager printed circuit board is adjusted relative to the lens holderand lens barrel construction to optically align the lens at the imager;wherein, after the imager printed circuit board is secured relative tothe lens holder, the lens barrel is rotated to adjust focus of the lensat the imager; and wherein the biasing element comprises a springelement disposed at the imager printed circuit board so as to act on thethreaded inner end of the lens barrel when the imager printed circuitboard is attached to the lens holder.
 11. A method for assembling avehicular camera, the method comprising: providing a lens barrelaccommodating a lens and having a threaded inner end; providing a lensholder comprising a threaded passageway; providing an imager printedcircuit board, wherein the imager printed circuit board comprises afirst side and a second side opposite the first side and separated fromthe first side by a thickness of the imager printed circuit board, andwherein an imager is disposed at the first side of the imager printedcircuit board; threadedly inserting the threaded inner end of the lensbarrel into the threaded passageway of the lens holder; applying abiasing force at the lens barrel to urge the lens barrel in a directionaway from the lens holder; after the lens barrel is threadedly insertedinto the lens holder, positioning the imager printed circuit board atthe lens holder and optically aligning the lens at the imager viamovement of the imager printed circuit board relative to the lensholder; attaching the imager printed circuit board to the lens holderwith the first side of the imager printed circuit board and the imagerfacing the lens and with the lens optically aligned with and focused atthe imager; after the imager printed circuit board is attached to thelens holder, rotating the lens barrel to adjust focus of the lensrelative to the imager; and providing a rear housing and attaching therear housing to the lens holder to encase the image printed circuitboard within the vehicular camera.
 12. The method of claim 11, whereinthe step of rotating the lens barrel to adjust focus of the lensrelative to the imager is performed after the rear housing is attachedto the lens holder.
 13. A method for assembling a vehicular camera, themethod comprising: providing a lens barrel accommodating a lens andhaving a threaded inner end; providing a lens holder comprising athreaded passageway; providing an imager printed circuit board, whereinthe imager printed circuit board comprises a first side and a secondside opposite the first side and separated from the first side by athickness of the imager printed circuit board, and wherein an imager isdisposed at the first side of the imager printed circuit board;threadedly inserting the threaded inner end of the lens barrel into thethreaded passageway of the lens holder; applying a biasing force at thelens barrel to urge the lens barrel in a direction away from the lensholder; after the lens barrel is threadedly inserted into the lensholder, positioning the imager printed circuit board at the lens holderand optically aligning the lens at the imager via movement of the imagerprinted circuit board relative to the lens holder; attaching the imagerprinted circuit board to the lens holder with the first side of theimager printed circuit board and the imager facing the lens and with thelens optically aligned with and focused at the imager; wherein attachingthe imager printed circuit board to the lens holder comprises adhesivelyattaching the imager printed circuit board to the lens holder with anadhesive and curing the adhesive to fix the imager printed circuit boardat the lens holder; and after the imager printed circuit board isattached to the lens holder, rotating the lens barrel to adjust focus ofthe lens relative to the imager.
 14. The method of claim 13, wherein thestep of rotating the lens barrel to adjust focus of the lens relative tothe imager is performed after the adhesive is cured.
 15. The method ofclaim 13, wherein the adhesive, in its uncured state, allows formovement between the imager printed circuit board and the lens holder inall directions during assembly of the vehicular camera.
 16. A method forassembling a vehicular camera, the method comprising: providing a lensbarrel accommodating a lens and having a threaded inner end; providing alens holder comprising a threaded passageway; providing an imagerprinted circuit board, wherein the imager printed circuit boardcomprises a first side and a second side opposite the first side andseparated from the first side by a thickness of the imager printedcircuit board, and wherein an imager is disposed at the first side ofthe imager printed circuit board; threadedly inserting the threadedinner end of the lens barrel into the threaded passageway of the lensholder; applying a biasing force at the lens barrel to urge the lensbarrel in a direction away from the lens holder; wherein applying thebiasing force comprises disposing a biasing element at least partiallybetween threads of the threaded inner end of the lens barrel and threadsof the threaded passageway of the lens holder; after the lens barrel isthreadedly inserted into the lens holder, positioning the imager printedcircuit board at the lens holder and optically aligning the lens at theimager via movement of the imager printed circuit board relative to thelens holder; attaching the imager printed circuit board to the lensholder with the first side of the imager printed circuit board and theimager facing the lens and with the lens optically aligned with andfocused at the imager; and after the imager printed circuit board isattached to the lens holder, rotating the lens barrel to adjust focus ofthe lens relative to the imager.
 17. The method of claim 16, wherein thebiasing element comprises a pliable material.
 18. The method of claim17, wherein the pliable material comprises a compressible elastomericmaterial.
 19. The method of claim 11, wherein applying the biasing forcecomprises disposing a biasing element at the lens holder to act on thethreaded inner end of the lens barrel when the threaded inner end of thelens barrel is threaded into the threaded passageway of the lens holder.20. A method for assembling a vehicular camera, the method comprising:providing a lens barrel accommodating a lens and having a threaded innerend; providing a lens holder comprising a threaded passageway; providingan imager printed circuit board, wherein the imager printed circuitboard comprises a first side and a second side opposite the first sideand separated from the first side by a thickness of the imager printedcircuit board, and wherein an imager is disposed at the first side ofthe imager printed circuit board; threadedly inserting the threadedinner end of the lens barrel into the threaded passageway of the lensholder; applying a biasing force at the lens barrel to urge the lensbarrel in a direction away from the lens holder; after the lens barrelis threadedly inserted into the lens holder, positioning the imagerprinted circuit board at the lens holder and optically aligning the lensat the imager via movement of the imager printed circuit board relativeto the lens holder; attaching the imager printed circuit board to thelens holder with the first side of the imager printed circuit board andthe imager facing the lens and with the lens optically aligned with andfocused at the imager; wherein applying the biasing force comprisesdisposing a biasing element the imager printed circuit board to act onthe threaded inner end of the lens barrel when the imager printedcircuit board is attached to the lens holder; and after the imagerprinted circuit board is attached to the lens holder, rotating the lensbarrel to adjust focus of the lens relative to the imager.
 21. A methodfor assembling a vehicular camera, the method comprising: providing alens barrel accommodating a lens and having a threaded inner end;providing a lens holder comprising a threaded passageway; providing animager printed circuit board, wherein the imager printed circuit boardcomprises a first side and a second side opposite the first side andseparated from the first side by a thickness of the imager printedcircuit board, and wherein an imager is disposed at the first side ofthe imager printed circuit board; threadedly inserting the threadedinner end of the lens barrel into the threaded passageway of the lensholder; applying a biasing force at the lens barrel to urge the lensbarrel in a direction away from the lens holder; after the lens barrelis threadedly inserted into the lens holder, positioning the imagerprinted circuit board at the lens holder and optically aligning the lensat the imager via movement of the imager printed circuit board relativeto the lens holder; attaching the imager printed circuit board to thelens holder with the first side of the imager printed circuit board andthe imager facing the lens and with the lens optically aligned with andfocused at the imager; wherein applying the biasing force comprisesdisposing a spring element at the imager printed circuit board to act onthe threaded inner end of the lens barrel when the imager printedcircuit board is attached to the lens holder; and after the imagerprinted circuit board is attached to the lens holder, rotating the lensbarrel to adjust focus of the lens relative to the imager.
 22. Avehicular camera configured to be disposed at a vehicle so as to have afield of view exterior of the vehicle, the vehicular camera comprising:a lens barrel accommodating a lens, the lens barrel having a threadedinner end; a lens holder comprising a threaded passageway for threadedlyreceiving the threaded inner end of the lens barrel; an imager printedcircuit board, wherein the imager printed circuit board comprises afirst side and a second side opposite the first side and separated fromthe first side by a thickness of the imager printed circuit board, andwherein an imager is disposed at the first side of the imager printedcircuit board; wherein the lens barrel is threadedly attached to thelens holder, and wherein a biasing element applies a biasing force atthe lens barrel to urge the lens barrel in a direction outward away fromthe lens holder; wherein the imager printed circuit board is attached tothe lens holder with the first side of the imager printed circuit boardand the imager facing the lens, and wherein the imager printed circuitboard is adjusted relative to the lens holder and lens barrelconstruction to optically align the lens at the imager; a rear housingthat is mated with the lens holder, with the imager printed circuitboard attached to the lens holder, to encase the imager printed circuitboard; wherein, after the imager printed circuit board is securedrelative to the lens holder and after the rear housing is mated with thelens holder, the lens barrel is rotated to adjust focus of the lens atthe imager; and wherein an electrical connector portion of the rearhousing is configured to electrically connect to a wire harness of avehicle equipped with the vehicular camera.
 23. The vehicular camera ofclaim 22, wherein the biasing element comprises a compressibleelastomeric material.
 24. The vehicular camera of claim 23, wherein thecompressible elastomeric material comprises a rubber material.
 25. Thevehicular camera of claim 23, wherein the biasing element is disposed atleast partially between threads of the threaded inner end of the lensbarrel and threads of the threaded passageway of the lens holder. 26.The vehicular camera of claim 23, wherein the biasing element isdisposed at the lens holder and acts on the threaded inner end of thelens barrel when the threaded inner end of the lens barrel is threadedinto the threaded passageway of the lens holder.
 27. The vehicularcamera of claim 23, wherein the biasing element is disposed at theimager printed circuit board and acts on the threaded inner end of thelens barrel when the imager printed circuit board is attached to thelens holder.
 28. The vehicular camera of claim 22, wherein the biasingelement comprises a spring element disposed at the imager printedcircuit board so as to act on the threaded inner end of the lens barrelwhen the imager printed circuit board is attached to the lens holder.